Waste disposal apparatus



Oct.20, 1970 w. A. LAWRENSON 3,534,913

WASTE DISPOSAL APPARATUS Filed May 23, 1967 5 Sheets-Sheet 1 iMvEMroR; LJILUAM ARTHufi LAmRMSo/d Oct. 20, 1970 w. A. LAWRENSON 3,534,913

WASTE DISPOSAL APPARATUS Filed May 23, 1967 s Sheets-Sheet 2 Fig. 2.

luvmofii (AMLLJAM Aame LJWM SOAL Oct. 20, 1970 w. A. LAWRENSON 3534913 WASTE DISPOSAL APPARATUS Filed May 23, 1967 3 Sheets-Sheet 3 UMLLHQH W LAMQQISOM A6 eur US. Cl. 24136 3 Claims ABSTRACT OF THE DISCLOSURE A waste disposal apparatus for mounting beneath a sink outlet and having an upper part which provides the walls of a grinding chamber, an inlet for the chamber at the upper end and an outlet from the chamber in the side wall adjacent the lower end of the chamber. The lower part of the apparatus is secured to the upper part by clips and the lower part provides a bottom wall of the chamber and supports a rotary impeller disposed between the inlet and the outlet. The lower part of the apparatus can be replaced by a closing plate when the lower part is removed for repair of either the impeller or the motor which drives it.

BACKGROUND OF THE INVENTION Field of the invention The invention relates to waste disposal apparatus which receive water and waste material and disintegrate the waste material by shredding to convert it to a condition suitable for discharge into a sewer.

Description of the prior art Previous forms of waste disposal apparatus have included casings of circular cross-section which enclose a chamber, the chamber being provided at its upper end with an inlet for connection to a sink outlet and with an outlet at the lower end of the chamber for the discharge of disintegrated waste material. A rotatable impeller is mounted in the chamber between the inlet and the outlet and divides the chamber into an inlet portion and an outlet portion. Such waste disposal apparatus are shown, for example, in US. Patent specifications Nos. 2,772,836 and 2,679,981. The unit shown in the latter specification includes an arrangement in which the impeller and its driving motor can be removed from within the casing but the separation of the motor and the impeller from the casing renders the sink outlet unusable and involves the untightening of a number of bolts.

SUMMARY The present invention provides a waste disposal apparatus as set out above in which the casing is formed in two separate parts, a first having the inlet and the outlet and a second carrying the rotary impeller and the motor means. Quick release fastener means are provided on said first and second parts to secure them together and a closing plate is provided for fitment to the first part in place of the second part if, for any reason, the second part is removed.

With this arrangement, should the apparatus become jammed or blocked, the user can easily undo the quick release fastener means, remove the part having the impeller and the motor and can thus unjam the impeller and clean out both the inlet and the outlet portions of the chamber. If a fault develops in the motor or in the impeller, the user of the apparatus will detach the second part of the casing and return it together with the motor and the impeller to the factory or a service depot for servicing or replacement. Meanwhile, the closing plate is United States Patent O Patented Oct. 20, 1970 secured in position to the first part of the casing so as to enable the user of the apparatus to continue to use the sink outlet.

The impeller may be mounted on the shaft of an electric motor, the shaft being fixed to and extending from the motor rotor into the outlet portion of the chamber and being supported for rotation only by bearings located between the rotor and the impeller.

Normally, the inlet portion of the chamber will be above the impeller and the outlet portion below the impeller. Furthermore, the driving motor for the impeller will normally be situated below it. In these circumstances, the shaft may be supported by two spaced bearings and the lower end of the shaft may carry the rotor which is otherwise unsupported. The rotor will rotate within a stator held within the casing.

BRIEF DESCRIPTION OF THE DRAWINGS The waste disposal apparatus shown in the drawings is adapted to be secured to the underside of the drainage outlet of a domestic sink and the apparatus includes an upper part and a lower part, the lower part being arranged to be detached from the upper part and a closing plate fitted in place of the lower part. In the drawings:

FIG. 1 is a vertical sectional view of the apparatus, showing the upper part and the lower part connected together.

FIG. 2 is a sectional view at right angles to FIG. 1 showing mainly the lower part and the sealing arrangement between the upper part and the lower part, and

FIG. 3 is a sectional view in the same plane as FIG. 1 and showing a closure plate fitted in place of the lower part of the apparatus.

DESCRIPTION OF THE PREFERRED EMBODIMENT end, a flange 12 which can be secured to the sink by any conventional means, the arrangement shown in FIG. 1 being purely by way of example.

The casing is arranged vertically and the upper part 10 diverges downwardly from the flange 12 and, at the lower part of the divergent section 13 of the casing, there is provided an upper cylindrical section 14. Beneath said upper cylindrical section 14 there is a lower cylindrical section 15 of larger external diameter than the upper cylindrical section 14 but the two sections 14 and 15 have the same internal diameter. Mounted within the two sections 14 and 15 is a shredding ring 16 which is formed from cast steel and is machined to the required configuration. The shredding ring 16 has an annular array of teeth 17 which extend vertically and the teeth 17 are equiangularly spaced around the inner periphery of the ring 16. The grooves between the teeth 17 may diverge downwardly so that the teeth have a slight downwards convergence. Above the vertically extending teeth 17 the ring 16 carries three impact teeth, one of which 18 is shown in FIG. 1. The teeth 18 are spaced apart around the periphery of the ring 16 and each tooth 18 has a flat face which is presented inwardly and the flanks 19 of the teeth 18 are inclined to the vertical and are stepped, the flanks converging'from the top of a tooth 18 to the bottom thereof. From their tips the impact teeth have the form of triangles the apices of which are directed downwardly and the sides are stepped.

The lower part 11 of the casing includes a domed member 20 and a generally cylindrical member 21 formed integrally with the domed member 20 and extending downwardly therefrom. Member 20 is provided on its upper surface with a peripheral recess which receives a rubber sealing gasket 22 and the domed member 20 fits within the lower portion 23 of the upper casing part, so as to form a spigot and socket joint therewith, with the sealing member 22 engaged in the recess in the domed member and abutting a shoulder 24 of the lower portion 23 so as to make a liquid-tight seal which is assisted by a sealing ring 25 which is located in a groove in the number 20 and bears against a part 26 of the lower portion 23 of the upper casing part 10.

The domed member 20 has a depending peripheral flange 27 which interconnects the domed member 20 and the cylindrical member 21 and the member 21 is provided at its lower end with a part of reduced thickness on which a closure cap 28 is fitted as a push-fit engagement with the member 21.

Centrally of the domed member 20 there is provided a boss 29 which extends both above and below the member 20. The boss 29 includes an inwardly directed flange 30 and there is a ball bearing assembly 31 immediately below the flange 30 and a further ball bearing assembly 32 at the lower end of the boss 29, the two assemblies being spaced apart by a spacer, 33.

A vertical shaft 34 of an electric motor 35 is received in the two bearing assemblies 31 and 32 and the shaft 34 is secured at its lower end to the motor rotor 36 which is not otherwise located or supported. The cylindrical member 21 carries the motor stator 37 so that the rotor 36 is hung within the stator 37 by means of the bearings 31 and 32. Above the upper bearing 31 there is provided a bush 38 which fits on the shaft 34 and the bush 38 has a flange 39. Above the flange 39 there is provided a face seal 40 which is of proprietary type and includes a rubber gaiter 41 having a helical spring 42 therein. The face seal provides a seal between the upper end of the boss 29 and the lower face 43 of an impeller 44 which is carried by the motor shaft 34. The impeller 44 is secured to the shaft 34 by means of a nut 45.

The impeller 44 is located in the chamber defined by the upper part of the casing and divides said chamber into a portion 46 which communicates with the inlet 47 and is disposed above the impeller and a portion 48 which communicates with the outlet 49 and is disposed beneath the impeller 44.

The impeller 44 is of the shape described in British patent specification No. 1,040,699, that is to say it includes a disc which carries a pair of diametrically opposed, radially extending ribs 50 and 51 which project from the disc upwardly towards the casing inlet and move around in the inlet portion 46 of the chamber and within the shredding ring 16 as the impeller rotates. The upper edge 52 of each rib 50, 51, is formed intermediate its end with a notch 53 so that each rib provides inner and outer projections nearer to and further from the rotational axis of the impeller 44 respectively. The end of each rib 50, 51 furthest from the axis co-operates with the vertically extending teeth of the shredding ring 16 to disintegrate waste matter introduced through the inlet 47. The impeller 44 is formed with a number of through apertures (not shown) and the periphery of the impeller is provided with a series of downwardly diverging recesses (not shown). Full details of the construction of the impeller can be obtained by reference to the specification referred to above.

The outlet 49 which is located in the lower cylindrical section 15 of the upper part 10 of the casing provides a connection with a spigot or pipe to lead the disintegrated waste and water from the apparatus to a sewer.

The upper and lower parts 10 and 11 of the casing are held together by means of three or more clips 54, the clips 54 being similar to the type normally used on luggage and similar cases. Each clip 54 includes a movable part which is mounted on the upper casing part 10 and the fixed parts 55 of the clips 54 are mounted on the lower casing part 11 by means of screws or rivets 56 which pass through the cylindrical member 21. When the two parts 10 and 11 of the casing are assembled together,

the domed member 20 of the lower casing part 11 closes the chamber within the upper part 10 of the casing, which chamber is divided into an inlet portion 46 and an outlet portion 48. When the clips 54 are engaged, the sealing members 22 and 25 between the two parts 10 and 11 provide a liquid-tight joint between the parts.

When the clips are engaged to hold the parts 10 and 11 together, the rod 57 is moved downwardly against the action of a spring 58 to operate a micro-switch 59, which micro-switch 59 is arranged, on downward movement of the rod 57, to complete a circuit of the motor stator 37. When the clips 54 are disengaged and the parts 10 and 11 are separated the rod 57 is free to move upwardly and the micro-switch 59 is deactuated and the electrical circuit of the stator 37 is broken thereby isolating the motor 35. This arrangement or any other corresponding interlock system ensures that, when the two casing parts 10 and 11 are separated, it is impossible for the motor 35 to be running to rotate the impeller 44. The provision of the rod 57 which is supported in a groove in the member 21 to avoid accidental depression gives the waste-disposal apparatus an important safety function.

The cap 28 which closes the lower end of the lower casing part 11 carries the micro-switch 59 and also carries a reset button 60, a relay 61, a capacitor 62 and the electrical supply cable gland 63.

In operation, waste matter is fed into the inlet 47 and is disintegrated between the shredding ring 16 and the impeller 44 and then passes between the impeller 44 and the ring 16, or through the holes in the impeller 44, into the outlet part 48 of the chamber and from thence into an outlet 49'.

Should the apparatus become jammed, the clips may be released and the lower part 11 of the casing can be removed complete with the impeller 44 and the motor 55. The jam can then be cleared and the parts speedily reassembled.

The apparatus is also provided with a closure plate 64 for fitment into the bottom of the upper part 10 of the casing, which closure plate 64 can be placed in position instead of the lower part 11 of the casing if any fault in the apparatus occurs which is not such that it can be corrected by the user of the apparatus. The user detaches the lower part 11 of the casing with the motor and the impeller and returns it either to the factory or to a service depot. Having removed the lower part 11 of the casing, the user inserts the closure plate 64 into the lower end of the upper part 10 of the upper casing and the closure plate 64 is provided with fixed clip parts 65 for engagement by the movable parts of the clips 54 carried by the upper part 10 of the casing which clips 54 are secured to the lower cylindrical section 15 by fasteners 66.

The closure plate 64 comprises a domed portion which has a downwardly depending peripheral flange 67. The flange 67 is stepped as can be seen from FIG. 3 and the part 68 of the closure plate between the domed portion and the flange 67 is arranged to abut against the sealing member 22 which is carried by the upper casing part 10 to provide a seal between the plate 64 and the part 10. Since the outlet of the waste disposal apparatus is in the upper casing part the sink can still be used when the closure plate 64 is in position and the user does not have to suffer the disadvantage which has arisen with previous forms of waste disposal apparatus of the kind specified in that he has been unable to use his sink when repairs have had to be effected to operating parts of the disposal apparatus.

Since the motor rotor 36 is suspended from above, the cap 28 can be formed as a simple pressing since it does not have to carry any load and does not have to provide a bearing for the motor shaft.

The advantages of a waste disposal apparatus constructed in accordance from the present invention will be apparent from the above description and it will be seen that the invention provides a Waste disposal apparatus which may, in many cases, be serviced by the user if it becomes jammed but which may be disassembled by the user and a defective part sent back for serving whilst the sink in which the apparatus is mounted can still be used.

What I then claim is:

1. Waste disposal apparatus comprising a casing adapted to be connected to an outlet from a sink and formed in two separate parts, a first of said casing parts having a comminuting chamber of which one end is open, an inlet for waste material and Water delivered through said sink outlet leading into the opposite end of said chamber, a lateral outlet for said waste material and water leading from said chamber adjacent to said open end, and a shredding ring carried within the chamber between the chamber inlet and outlet, the second of said casing parts having a motor chamber of which one end is closed by a wall, an electric motor located within said motor chamber and a rotary impeller located within the shredding ring and drivably connected to said motor, and quick release fastener means including movable members mounted on and externally of said first casing part and adapted to engage cooperating fixed members provided on and externally of said second casing part to secure said casing parts releasably together with said wall closing the open chamber end and said impeller disposed within the shredding ring, said movable members being readily disengageable from said co-operating fixed members so that the second casing part may be dismantled from the first casing part.

2. Waste disposal apparatus according to claim 1 further comprising an electric switch carried in the motor chamber and connected in the current supply circuit of the motor, and a spring-loaded, reciprocable switch actuating member extending from the interior of said motor chamher to the exterior of the chamber wall which closes the open end of the comminuting chamber, said actuating member being spring-biased in a switch-opening direction and being depressed in the opposite and switch-closing direction by the first casing part so that, upon disengaging the movable members of the quick release fastener means from the co-operating fixed members and separating the second casing part from the first casing part, said actuating member is spring-driven in said switch-opening direction to prevent operation of the motor except when the said casing parts are secured together.

3. Waste disposal apparatus according to claim 1 in which the motor chamber is defined by the wall of the second casing part which closes the open end of the first casing part, an annular portion integral with said wall, and a cap detachably assembled to the end of said annular portion remote from said wall, a stator of the motor is carried within said annular portion, a driving shaft extends through, is rotatable in and is carried by said wall, a rotor of the motor is carried by said shaft and is rotatable within the stator, and the impeller is carried by said shaft and is rotatable within the shredding ring.

References Cited UNITED STATES PATENTS 2,772,836 12/1956 Gebhart 241-1005 X 2,853,248 9/1958 Long 241-1005 X 2,978,190 4/1961 Brucken 241-1005 X 3,082,964 3/1963 Yartz 241-1005 3,165,270 1/1965 Stout 241-257 3,181,801 5/1965 Lung 241-46.08

FOREIGN PATENTS 1,158,221 11/1963 Germany.

ROBERT C. RIORDON, Primary Examiner D. G. KELLY, Assistant Examiner US. Cl. XR. 

